If A + B = 90° and cos B = 3/5, what is the value of sin A?

Question

Philoid · Accepted Answer

Given,

cos B = 3/5 and

A + B = 90°

So we have,

B = 90° - A

So,

cos B = cos (90° - A) = 3/5

∵ cos B = sin A

Therefore,

sin A = 3/5